GB2099329A

GB2099329A - Dust filter apparatus

Info

Publication number: GB2099329A
Application number: GB8116496A
Authority: GB
Original assignee: Coal Industry Patents Ltd
Current assignee: Coal Industry Patents Ltd
Priority date: 1981-05-29
Filing date: 1981-05-29
Publication date: 1982-12-08
Also published as: AU8425782A; DE3213642A1

Abstract

A filter element (2) provided across a gaseous flow duct (1) is constituted by two open mouth troughs, each trough comprising two intersecting filter surface portions (3 and 4) which are inclined relatively to each other and to the direction of gaseous flow along the duct. Nozzles (7) mounted longitudinally in line with the intersection (8) of the inclined portions (3 and 4) spray fluid into the mouths of the troughs. <IMAGE>

Description

SPECIFICATION Dust filter apparatus This invention relates to dust filter apparatus.

In particular, although not exclusively, the present invention relates to dust filter apparatus for use in underground mines where it is known to induce an air flow away from a dust generating source, for example, a rock cutting head or a conveyor dis charge station and to pass the induced air flow through the dust filter apparatus to remove particles of dust from the air.

Examples of prior known dust filter apparatus suitable for use in underground mines are disclosed in British Patent Specification Nos 1 412 299 and 1 544 462. Although these prior known filter apparatus are efficient for suppressing dust they suffer from the disadvantage that if a desirably small cross section is maintained they are incapable of handling heavy dust concentrations as frequently are encoun tered in some mining installations.

An object of the present invention is to provide dust filter apparatus which tends to overcome or reduce the above mentioned problem.

According to the present invention dust filter apparatus comprises a gaseous flow duct along which, in use, gas is induced to flow, a filter panel arranged across the duct and having a filter element adapted, in use, to arrest particles of solid material from the induced gaseous flow along the duct, and nozzle means mounted upstream of the filter panel for spraying liquid on to the filter panel, the filter element comprising two intersecting filter surface portions which are inclined relatively to each other and to the direction of induced gaseous flow along the duct so as to define a generally 'V' shaped open mouth trough with the open mouth of the trough facing upstream, the nozzle means comprising at least one nozzle mounted upstream of the trough and longitudinally in line with the intersection.

Preferably, the said at least one nozzle directs a spray into the open mouth of the trough.

Preferably, the intersection extends substantially vertically down the duct.

Advantageously, the filter element comprises at least two sets of intersecting filter surface portions each set defining a generally 'V' shaped open mouth trough.

Preferably, adjacent filter surface portions of adja cent sets of intersecting surface portions intersect to define an upstream directed edge.

Preferably, means are provided for extracting liquid flowing down the filter element from the gaseous flow duct.

By way of example only, one embodiment of the present invention will be described with reference to the accompanying drawing, in which: Figure 1 shows diagrammatically a section taken horizontally through filter apparatus constructed in accordance with the present invention; Figure 2 shows diagrammatically a section taken vertically through a filter apparatus of Figure 1; Figure 3 shows diagrammatically an end view of the filter apparatus of Figure 1; and Figure 4 shows a sectional view of a detail of Figure 1.

The drawings show the filter apparatus to comprise a gaseous flow duct 1 along which, in use, gas is induced to flow in a direction indicated by arrows X in Figures 1, 2 and 4. Typically the gas is airwhich is induced to flow along the duct by means of a fan (not shown) which may be mounted upstream or downstream of the filter apparatus.

A removable filter panel 2 comprising a filter ele ment 13 is arranged across the duct to arrest particles of solid material from the induced gaseous flow along the duct. As seen in Figure 4 the filter element comprises a protective pre-filter screen component 14 for removing coarse particles from the gaseous flow, an active filter component 15 for removing relatively fine dust particles from the gaseous flow, and a rigid backing support component 16 located on the downstream side of the filter component.The filter element is made up of four relatively inclined portions arranged in two sets of filter surface portions, each set comprising two intersecting filter surface portions 3 and 4 which are inclined relatively to each other and to the direction of induced gaseous flow X so as to define a generally 'V' shaped open mouth trough with the open mouth of the trough facing upstream with respect to the gaseous flow along the duct. The intersection 8 of the two surface portions 3 and 4 constituting the base of the associated trough extend vertically down the duct.

The two relatively innermost surface portions 3 and 4 (as seen in Figure 1) intersect to define an upstream directed edge 5. The upstream margins of the two relatively outer most surface portions are connected by brackets (not shown) to the side walls of the removable filter panel frame. In addition, brackets (not shown) sealably connect the surface portions to the floor and roof of the panel frame.

A back of nozzles 7 located upstream of the filter panel is arranged such that each nozzle is mounted upstream of its associated trough and arranged longitudinally in line with the intersection 8 constituting the base of the associated trough such that, in use, each nozzle directs a spray of fluid, eg water, into the open mouth of the trough. The nozzles 7 are fed with fluid via pipe work 10.

A water eliminator 24 comprising a plurality of corrugated plates 25 (only some of which are shown) in Figure 1 is provided within the duct downstream of the filter panel to remove excess water carried over from the filter panel by the gaseous flow.

The floor of the duct is provided with water removal passages 26 for removing water flowing down the filter element 2 and passing through holes 30 in the panel floor upstream of the filter element and down the water eliminator 24. Baffle plates 27 are provided to prevent substantial quantities of the gaseous flow from bypassing the filter panel and water eliminator. Normally the gap between the bot The drawing originally filed was informal and the print here reproduced is taken from a later filed formal copy. tom of the baffle plates and the floor of the filter apparatus is closed by water draining from the filter and water eliminator. It will be appreciated that dust particles including coarse material are carried along by the water and washed out of the filter apparatus.

Thus, no build up of particles takes place and a substantially continuous operation is maintained.

In use in an underground mine installation the filter apparatus is inserted in a ventilation ducting system extracting air from a relatively dusty zone. The air is induced to flow along the ducting system towards the filter apparatus. As stated previously the fan inducing the airflow may be mounted upstream or downstream of the filter apparatus.

Upon reaching the filter apparatus the air is wetted by water sprays from the nozzles 7, the water saturating the filter element over its full surface area and throughout its thickness.

The wetted particle of solid material are arrested by the filter element and washed down the element by the water from the nozzles 7. The inclined portions 3 and 4 effectively increasing the working area of the filter element when compared with the cross-sectional area of the duct. The nozzles 7 are located longitudinally in line with the intersection 8 of the associated trough in order to maximisethe effect of the sprays.

Any surplus water carried over from the filter element by the treated relatively duct free air is removed by the water elimination 24. The treated air then is fed back into the ventilation airflow of the main.

In other embodiments of the present invention at least one of the nozzles 7 is arranged to direct a spray of water upstream of the gaseous airflow.

Claims

1. Dust filter apparatus comprising a gaseous flow duct along which, in use, gas is induced to flow, a filter panel arranged across the duct and having a filter element adapted, in use, to arrest particles of solid material from the induced gaseous flow along the duct, and nozzle means mounted upstream of the filter panel for spraying liquid on to the filter panel, the filter element comprising two intersecting filter surface portions which are inclined relatively to each other and to the direction of induced gaseous flow along the duct so as to define a general 'V' shaped open mouth trough with the open mouth of the trough facing upstream, the nozzle means comprising at least one nozzle mounted upstream of the trough and longitudinally in line with the intersection.

2. Apparatus as claimed in claim 1, in which the said at least one nozzle directs a spray into the open mouth of the trough.

3. Apparatus as claimed in claim 1 or2, in which the intersection extends substantially vertically down the duct

4. Apparatus as claimed in claim 1,2 or 3, in which the filter element comprises at least two sets of intersecting filter surface portions each set defin ing a generally 'V' shaped open mouth trough.

5. Apparatus as claimed in claim 4, in which adj acent filter surface portions of adjacent sets of intersecting surface portions intersect to define and upstream directed edge.

6. Apparatus as claimed in any one of the preceding claims, in which means are provided for extracting liquid flowing down the filter element from the gaseous flow duct.

7. Duct filter apparatus substantially as described herein and substantially as shown in the accompanying drawings.